Hot-air furnace



D. S. RICHARDSON.

(No Model.)

HOT .AIR FURNACE.

Patented Oct. 15, 1889.

I M I a am M N. PETERS. Phoxo-Lilhogmphur. Washington. 0. c.

UNITED STATES PATENT OEricE.

DWVIGHT S. RICHARDSON, OF BROOKLYN, NEW YORK.

HOT-AIR FU RNAC E.

SPECIFICATION forming part of Letters Patent No. 412,860, dated October 15, 1889.

Application filed October 3, 1888. Serial No. 287,073. (No model.)

both sides of which the products of combustion pass on their way to their point of eXit from the furnace, the function of suchplate or diaphragm being to change the direction of the escaping heat-currents and to insure their retention within the radiator until the greater portion of their caloric shall have been radiated into the warm-air chamber of the furnace for utilization.

Hitherto it has been found extremely difficult, in constructing and operating this class of furnaces, to provide a diaphragm or flueplate which would for any considerable period resist the destructive action of the volatile products of combustion, the only construction of heavy radiator which has proven at all effective being that in which the diaphragm is cast with the body of the radiator, as provided in United States Patent No. 272,326, issued to me on the 13th of February, 1883.

The radiator described in that patent hasbeen operated with satisfactory results in all situations in which a high degree of heat maintained continuously for a long period In the drawings,Figure].represents a side elevation of a furnace provided with my improved radiator, portions being broken out of the wall thereof to show the direction of the smoke-currents in their passage through the same. Fig. 2 represents a transverse vertical section in the line w w of 1. Fig. 3 represents a transverse vertical section of a radiator of modified form.

The ash-pit a, the fire-pot a, and the combustion-chamber a of the furnace A may be of any ordinary or approved construction. The body or exterior wall of the radiator A, receiving the smoke and gases from the combustion-chamber and discharging the same into the uptake, is composed either of sheet metal or of very thin cast metal. Upon the inner surface of its walls the radiator is pro vided, bypreference, with a supporting-ledge, or with a series of brackets a upon or against which rests the diaphragm or fiueplate A composed, as already explained, of fire-brick or other refractory material.

It will be understood that in the radiator represented in Fig. 3 the side walls are of thin @metal, while the top plate and the bottom plate are of heavy cast metal. The fiue-plate or diaphragm being very thick, as shown, will absorb a large portion of the heat contained in the first-received smoke currents, and when thus charged with caloric will be of nearly uniform temperature throughout, and will consequently be but slightly, if at all, affected by the disparity in temperature between the incoming and outgoing smoke-currents, while the thinness heating-drum which is divided by a detachtile products of combustion, substantially as able diaphragm into an incoming and an described. outgoing flue, the body of the radiator being composed of thin quickly-radiating metal, DWIGHT RICHARDSON the diaphragm being composed of fire-brick Witnesses:

or like refractory material and serving to HENRY T. RICHARDSON,

reverse the direction'of the flow of the vola- J AS. B. TAYLOR 

